insulation... why so little?

Mitch_4

Is the density (in pounds per sq ft) Having attended the training seminar on the forced air units I use, the insulation weight has quadrupled from 1/2 to 2 lbs per sq ft, and the foil face reflects the radiant energy back.

In a boiler I agree with another poster about the wasted heat. Overall more would be lost via exposed pipe than the heat exchanger. A cast iron unit would be about the same as 5 - 8 feet of baseboard..from H2O content and that is about all.

Some euro units I hear have like 3" but wha tis the density? is it foil faced, what is the r value.. it is all a factor.

walls 2' thick with a r6 value are not betther than a 4" wall r-20.

thickness is a factor, but there is more to it than that.

Mitch

John S.

A question for boiler manufacturers

Why is it that the amount of insulation on todays boilers is so little?

The half inch that my new Peerless steamer came with seems negligible. The Weil that it replaced was the same. Wouldn't it make sense to insulate this big hunk of cast iron better?

To Learn More About This Professional, Click Here to Visit Their Ad in "Find A Professional"

TCR_2

minimal insulation

My new Peerless EC/ECT is the same way. I opened the jacket and carefully cut fibreglass insulation to fit in the major voids that were just empty spaces.

I thought about building a box out of Thermax rigid insulation around the whole boiler (excpet the front). In theory with a 1" air gap between the boiler jacket and the reflective face of the insulation there should be a big reduction in the radiated heat from the boiler.

Thermax is rated to 250*F but there may be safety and other issues.

rumn8r

I'm not 100 % sure....

but I think it has to do with the AFUE ratings. The faster a device looses heat to the space it is heating in standby mode, the higher the AFUE rating it gets...

Someone please correct me if I am mistaken.

In the case of mod cons, the differential temperature is so low, that in some cases, no insulation is provided at all (see Knight Mod Con).

Makes no sense to me...

BTW, you won't see that in European boilers, but then again they don't make steam boilers for residential space heating any more. Wonder why that is:-)

ME

jp_2

surface area

i look at it this way for a low mass boiler:

heat excharger looks like a coffee can, minimum surface area conpared to volume, boilers near by piping has a lot of surface area for little volume, just the opposite.

the nearby piping has the ability to loose far more heat than the excharger, so is heavily insulating the excharger going to make a big difference? i'd say not really!

kind of like why insulate a wall when 85% of it is glass?

EDIT:
remember too, the excharger is not a storage tank, that little approximate gallon of water in there isn;t going to have much impact if it dissipates to the surroundings.

Capetom

As a home owner with an older oil fired boiler with tankless coil, I was wondering about adding a layer of insulation (safely of course). I can't help but think that approx 2' x 3' metal surface at the back of the boiler is radiating a lot of heat into my basement and contributing the majority of standby losses. Any thoughts on that?
Thanks.

John Ketterman

Insulation would only make sense if the basement, or wherever your boiler is, is outside the house's envelope. Basements rarely are. They may be slightly cooler than upstairs, but they're still much warmer than the outdoors on a cold day, so they're inside the envelope. If the basement doesn't get any heat from the boiler, it'll draw more heat from upstairs. It's a wash.